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991.
The snake venom toxin alboaggregin-A activates glycoprotein VI   总被引:2,自引:2,他引:0  
The glycoprotein (GP)-Ib-IX-V receptor complex has recently been reported to signal through a pathway similar to that used by the collagen receptor GPVI, with a critical role described for the Fc receptor gamma-chain. The evidence for this was based in part on studies with the GPIbalpha-selective snake venom toxin, alboaggregin-A. In the present study, it is reported that alboaggregin-A has activity at the collagen receptor GPVI in addition to GPIbalpha, and evidence is provided that this contributes to protein tyrosine phosphorylation, shape change, and GPIIb-IIIa-dependent aggregation. This may explain why responses to alboaggregin-A are distinct from those to von Willebrand factor-ristocetin. (Blood. 2001;97:3989-3991)  相似文献   
992.
993.
Using data obtained during a retrospective interview study of 30 women who had undergone genetic testing-BRCA1/2 mutation searching-this paper describes how women, previously diagnosed with breast/ovarian cancer, perceive their role in generating genetic information about themselves and their families. It observes that when describing their motivations for undergoing DNA testing and their experiences of disclosing genetic information within the family these women provide care based ethical justifications for their actions. Finally, it argues that generating genetic information and disclosing this information to kin raise different types of ethical issues. The implications of these findings for ethical debates about informed choice in the context of genetic testing are discussed.  相似文献   
994.
995.
Existing criteria used to evaluate information on the World Wide Web often are not related to nursing, especially in relation to clinical and evidence-based practice. Published criteria have been found orientated to the health-consumer, medicine, or general information. In this study, the process by which nurses evaluate practice-related information and the associated evaluative nursing criteria were investigated using a grounded theory approach. In the first stage of this ongoing investigation, semistructured interviews were used to collect data from UK postregistration nursing students. The findings from this initial study provided indications of the process and the criteria for evaluating information on the World Wide Web. Participating students identified intuition as part of the evaluative process. They identified some criteria similar to existing standards, but critically, with additional criteria that are nursing practice related. Because these new criteria are significant for evaluating nursing information, further refinement of these findings is being undertaken through the next stage of the research program.  相似文献   
996.
997.
This paper describes a study of perceptions of nursing by nursing students, qualified nurses (United Kingdom and Spain), patients and non-nursing students. A survey method was used with a longitudinal panel element incorporating a 35-item version of the Nursing Dimensions Inventory translated into Spanish. Data were analysed using principal component analysis, congruence analysis, Mokken scaling, correlation, ANOVA, t-test and Cronbach's alpha. Patients may perceive nursing differently from nursing students, nurses (in the UK and Spain) and non-nurses. These findings are discussed in the context of nurse education and patient care.  相似文献   
998.
Cerebral venous thrombosis is a rare condition affecting predominantly adolescents or young adults. The presentation is often non-specific, and delay in diagnosis is common. The otolaryngologist may be consulted about the radiological findings of lateral sinus thrombosis and mastoid changes. The association of congenital thrombophilia with unusual presentations of venous thrombosis, especially in young individuals is now well documented. We present a case of lateral and sagittal sinus thrombosis complicated by cerebral venous infarction in a girl with protein C deficiency and masked mastoiditis. Unusual forms of venous thrombosis, including cerebral venous thrombosis may develop in association with a single risk factor for thrombosis, but additional risk factors should be sought especially when thrombosis presents in very young individuals. This case draws attention to the multi-causal nature of cerebral venous thrombosis in young adults, and highlights the issue of masked mastoiditis. A coordinated approach by otolaryngological and haematological teams is recommended in such cases.  相似文献   
999.
This study reports the evolution of a newborn hearing screening program which began in 1988. Data are reported from the period of time that universal newborn hearing screening was initiated, i.e. April 1996 to December 2000 (total screened=7128 babies). From 1996 to the present, the program has developed to the current form. During 2000, 1713 infants in the well-baby nursery and neonatal intensive care unit were screened at a cost of 18.44 dollars per child. Thirty (1.7%) infants failed the screen, of which 26 (86%) returned for follow-up testing. Fifteen infants were documented with hearing loss, 10 with conductive and five with sensorineural losses. The false positive rate was 0.96% and the overall sensorineural impairment rate was 1/343.  相似文献   
1000.
"Attention" is not a unitary brain process. Evidence from adult studies indicates that distinct neuroanatomical networks perform specific attentional operations and that these are vulnerable to selective damage. Accordingly, characterising attentional disorders requires the use of a variety of tasks that differentially challenge these systems. Here we describe a novel battery, the Test of Everyday Attention for Children (TEA-Ch), comprising nine subtests adapted from the adult literature. The performance of 293 healthy children between the ages of 6 and 16 is described together with the relationships to IQ, existing measures of attention, and scholastic attainment. This large normative sample also allows us to test the fit of the adult model of functionally separable attention systems to the observed patterns of variance in children's performance. A Structural Equation Modelling approach supports this view. A three-factor model of sustained and selective attention and higher-level "executive" control formed a good fit to the data, even in the youngest children. A single factor model was rejected. There are behavioural and anatomical grounds to believe that Attention Deficit Disorder (ADD) is particularly associated with poor self-sustained attention and behavioural control. The TEA-Ch performance of 24 boys diagnosed with ADD presented here is consistent with this view. When performance levels on WISC-III subtests were taken into account, specific deficits in sustained attention were apparent while selective attention performance was within the normal range.  相似文献   
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